Posted
by
kdawson
on Sunday November 05, 2006 @06:14PM
from the green-light-turns-us-on dept.

Roland Piquepaille writes, "Researchers in California are now using light to control biological nanomolecules and proteins. They think it can help them to develop treatments for eye diseases, such as the loss of the light detectors in the retina that is a major cause of blindness. They envision putting some of their nano-photoswitches in the cells of the retina, restoring light sensitivity in people with degenerative blindness such as macular degeneration. It will be a while before this technique emerges from the laboratory. ZDNet has additional references and pictures of what you can do with these photoswitches."

While this is very cool research (and we are looking at hiring one of the graduate students involved in this project as a post-doc when he graduates), they are still not addressing many of the fundamental issues related to retinal degeneration such as retinal remodeling that we have addressed for the past couple of years. The problem is that the retina (like any other neural system) will remodel its connections when the inputs have been lost. In retinal degenerations, when the photoreceptors degenerate, you lose your inputs and any new input you put in, either bionic implant or biological transplant will have to deal with corrupted circuits.

Corrupted circuits or no, any advances in the field of optometry make me happy. I was born with one functioning eye, and any chance that I'm given to regain my other eye is a chance i'd be happy to take. (You know, as long as there is a reasonable chance of success, I'm not going to stab myself in the eye with a fork.) What I wouldn't give for true depth perception, instead of my ghetto rigged pictorial variety.
Hurray Science!

Well, we (the community of vision scientists) are working on vision rescue strategies and one of the goals at the Moran Eye Center is to assemble the best possible team we can to begin coherently working on solutions that will help resolve vision loss through development, disease and trauma. The problem with vision rescue approaches in the past little while is that they have not truly examined at a fundamental level some of the basic science involved in the neural processing of the retina. But now that we

Does the visual cortex also 'remodel' when being deprived of input? If so, would it 'remodel' back after a period of time once input has been restored?
Perhaps an alternative, although understandably more complex alternative would be to interfere with the optic nerve directly.

It is an interesting question that nobody has yet (unbelievably) addressed adequately. My guess is that we are going to see cortical and subcortical remodeling in any system that has been deafferented much like we see from the learning and memory literature or the epilepsy literature. Wanna job doing some of the research?:-)

If so, would it 'remodel' back after a period of time once input has been restored?

"Wanna job doing some of the research?:-)"
I'd love to:), but not only am I inadequately travelled in the arts of biology, if there is a god, he is guaranteed to smite me for tinkering with his inferior creation.
My curiosity drives me towards the auditory system, but then again my curiosity also drives me towards the releasing of the mind from this slab of beef we call our home, which in itself would by default take care of all the other problems:)

Instead of hoping for an advancement in science to give you two good eyes, you should be concentrating on finding a place where everyone is blind. I've heard places like that look for someone like you to make their king...:-)

Yes, well, if you were the poster, I would send my heartfelt, genuine apologies for a joke that was evidently in bad taste in so far as it made you feel bad. As it is, you are AC, so I really don't care what you have to say.

I'm sorry about your macular degeneration, and I apologize if I seemed to make light of the condition of not being able to see. I actually have macular degeneration in my family (although it hits us at old age), and the disease scares the hell out of me. I know that doesn't compare with, you know, actually having the disease, but I do take blindness seriously. I thought I was following the tone of the original poster, who made reference to his "ghetto rigged pictorial variety" of depth perception. I probabl

Looks like I should have commented sooner.
That joke was hilarious, I see no reason why you should be modded flamebait, since, you know, if there was a land blind people I WOULD be their king.
Hurray sense of humor!

I should say, that MrPeebles comment was directed to me and not the half-blind community as a whole. I should also say that I found it funny, as well as assure everyone who reads this in the future that I am not the whiney AC.
Go you mrpeebles, go you.

Doesn't the idea of artifical receptors (and actuators) assume neuronal adaptation in the first place? It's not like the surgeons could manually reconnect every neuron in your optic nerve to the correct pin on a chip.

... they could restore sight, but with 100 times the clarity (think more pixels) than human sight? Would the brain be able to cope with this? Would baseball players be able to bat.800 because they could see the seams of the ball better? Is there anything that fundamentally prevents some kind of development like this from happening?

Actually, we only consciously "see" with about 20% of our ganglion cells. The other 80% project to other areas of cortex and subcortical regions that mediate percepts of movement and circadian timing among other things. The other thing that you should remember is that it is not compression of information per se, so much as it is filtering and pre-processing of information in a parallel fashion prior to transmission to other CNS regions.

I don't believe visual clarity helps you hit a fastball. I think it has more to do with speed, or more specifically, how fast your brain can process the input and determine when/where to swing the bat. If your brain could work fast enough to allow you to perceptually slow down time (making it seem like you had plenty of time to choose the best moment and angle to swing the bat), you may be able to bat close to 1000.

It turns out that for things such as hitting a fastball etc..., the visual system actually performs predictive processing and helps you to kinesthetically program a response based upon a prediction of where an object, such as a baseball will be at the appropriate time. You don't actually "see" the ball along its entire path.

How fast your brain can process the input is normally based on how fast the neurochems travel through the neurons. Maybe they will come up next with some nanomachines that may allow for a faster transport thus giving you and effective increase in response time, so as to process the information faster and actually hit every single ball.
although all this really sounds like SciFi to me

I don't think you could do this by adding more receptors to the retina; there are only so many nerves running to the vision center. Further, the vision center depends on inputs being related to each other, so you couldn't "squeeze" new ones in. I think you'd need to replace the entire vision center.On the other hand, you could design the receptors so they could also take an external signal, letting a computer feed a zoomed image, or a false-color image including IR/UV or other spectra, to the retina and f

Good point. Who knows? What I _can_ tell you (as a physician) is that most of the "brain" part of the vision process happens in the first months after birth. If you take a newborn and blindfold it for 24 months, it will be blind for life - due to cortical blindness. The eye works, the nerve works, but the part of the occipital lobes that process vision just don't process it properly anymore.

Because of this I doubt very much that an adult with regular vision can have their vision "enhanced" at all.

Ah, but if we introduce all of the "enhancements", such as additional spectral filters or channels into the existing channels as biological additions (or bionic implants), then we can piggyback enhancements on existing circuitry.

i think bwjones meant that we could map other kinds of non-visible energy (uv, infrared just to name a few) to colours that we CAN see. then, just have some kind of a control that changes the mapping, and you can see heat, magnetism, radiation or anything else with the press of a button.

AFAIK the limiting factor in the average, healthy eye is not the density of the optical receptors but the quality of the optical apparatus that projects the image onto the retina. Think megapixel camera chip in a cell phone with cheap optics. More exactly, the density of the optical receptors suggests that a visual acuityhttp://en.wikipedia.org/wiki/Visual_acuity [wikipedia.org] of 20/10 is the maximum possible with a perfect optical apparatus. In real life, only a few lucky individuals have that good eyesight. Most of us a

As another poster has said, the brain drops 90% of all input from the eyes. Secondly, our eye cannot process even 1% of the light rays/photons that go into it so our brain does approximations.This is the reason why optical illusions work on us and we can see objects in clouds and various other issues to why humans hallucinate.

However, if we were to make a "cyborg baseball player" we could use other sensory input directly into the brain. Besides the optical, we could use a camera to calculate the speed, loca

Mad props to this guy for the successful self promotion. This technology really blurs the line between molecular biology and nanotechnology. Because the NIH and NSF have a massive woody for Nanotechnology at the moment, people must rebrand their science as such even if a different name like protein engineering would be more accurate. But they are using light too? This has been done before nano was a trendy word.Small interfering RNA [agingeye.net] has been used in human clinical trials [sirna.com] as a very safe way to treat age rela

Hey so they can give this to people who aren't blind?
If so then I want some. Think of my idea metaphorically as upgrading from 640x480 @ 16 bit color depth to 1600x1200 @ 32 bit color depth:D:D:D:D
Upgrading eye hardware sounds fun heh

When I was sandbox-age, my eyes were infected with toxoplasmosis (the bacteria that grows on kitty poo). It caused scar tissue to form on my retinas, rendering my left eye all but useless, and impaired my right to a moderate degree as well. If you look at magnified pictures of my retina, it's one of those textbook cases where even a layperson can look at it and say "whoah that's messed up".The lack of light receptors in my left retina occurs right in the center of the optical cortex, basically leaving me

> the loss of the light detectors in the retina that is a major cause of blindness.

the loss is NOT the final cause! restoring them is NOT a solution. it's only a poor man's temporary fix. like duct tape and a plastic plane for your window.this fix will solve the problem as much as the plastic plane stops anyone from throwing stones on the window!